Yeah, doesn't seem like Google is going to put effort into putting out any of their apps on the WP8 platform. I'd really like a G+ app as well. The iOS app is pretty awesome, especially with it's latest update. I don't particularly use G+ but it's great to read feeds from certain people/companies. But for now, the plain looking website is the only choice.

I released a Google+ client a few weeks ago that provides the ability to see posts in your circles, comment/+1 posts, and also add your own posts. You can also attach a photo and your current location to your posts as well. Since Google has no official Google+ API, the app is somewhat limited in what it can do, but I think it's the only native Metro/Modern-styled app for Google+ available now.